Correct minor typos in slide notes (#2687)

- There's a `NotCloneable` in the code, no `NonCloneable`
- Point<StderrLogger> doesn't make sense in this context

Author: ColinPitrat

src/closures/traits.md

@@ -2,7 +2,7 @@
 minutes: 10
 ---
 
-# Closures
+# Closure traits
 
 Closures or lambda expressions have types which cannot be named. However, they
 implement special [`Fn`](https://doc.rust-lang.org/std/ops/trait.Fn.html),

src/generics/generic-data.md

@@ -52,7 +52,7 @@ fn main() {
   - It is possible to write `impl VerbosityFilter<StderrLogger> { .. }`.
     - `VerbosityFilter` is still generic and you can use `VerbosityFilter<f64>`,
       but methods in this block will only be available for
-      `Point<StderrLogger>`.
+      `VerbosityFilter<StderrLogger>`.
 - Note that we don't put a trait bound on the `VerbosityFilter` type itself. You
   can put bounds there as well, but generally in Rust we only put the trait
   bounds on the impl blocks.

src/generics/trait-bounds.md

@@ -25,7 +25,7 @@ fn main() {
 
 <details>
 
-- Try making a `NonCloneable` and passing it to `duplicate`.
+- Try making a `NotCloneable` and passing it to `duplicate`.
 
 - When multiple traits are necessary, use `+` to join them.
 

src/std-traits/comparisons.md

@@ -72,10 +72,10 @@ impl PartialOrd for Citation {
 - In practice, it's common to derive these traits, but uncommon to implement
   them.
 
-- When comparing references in Rust, it will will compare the value of the
-  things pointed to, it will NOT compare the references themselves. That means
-  that references to two different things can compare as equal if the values
-  pointed to are the same:
+- When comparing references in Rust, it will compare the value of the things
+  pointed to, it will NOT compare the references themselves. That means that
+  references to two different things can compare as equal if the values pointed
+  to are the same:
 
   ```rust,editable
   fn main() {